This paper conducts an in-depth analysis of the current development status and future trends of underwater robots. From a technical perspective, it elaborates on the transformations brought by multidisciplinary technologies such as artificial intelligence to the intellectualization and high-performance upgrading of underwater robots. For instance, the manned submersible Fendouzhe has set a new national record for China’s manned deep-sea diving with its advanced technologies. In terms of application fields, this paper discusses the extensive applications of underwater robots in marine scientific research, ocean engineering, environmental protection and emerging industries. Specifically, underwater dredging robots have effectively solved the dredging difficulties of drainage facilities. By analyzing the market scale and competitive landscape, the paper presents the rapid growth and diversified competition of the industry. Meanwhile, it addresses the core challenges restricting industrial development, including technical bottlenecks, high operational and manufacturing costs, imperfect laws, regulations and industrial standards, as well as talent shortages. The research indicates that the underwater robot industry boasts broad development prospects. Multi-party collaboration among industries, universities and research institutions is required to make breakthroughs in key technologies, improve relevant laws, regulations and standards, so as to promote the sustainable and healthy development of the industry.